Check valve means for heat pumps



Jan. 24, 1967 R H 3,299,662

CHECK VALVE MEANS FOR HEAT PUMPS Filed Nov. 12, 1965 3 heets-Sheet l FIGI.

COMPRESSOR REVERSAL H VALVE RV r l3 1: INDOOR EXPANSION l7 puToooR AIR com "1i VALVE 2 AIR com OUTDYOOR 1% AIR COIL CHECK VALVE CYLINDER |NVENTOR= JAMES R.HARN|SH, BYQQW J @M ATTORNEY Jan. 24, 1967 Filed Nov. 12, 1965 J. R. HARNISH CHECK VALVE MEANS FOR HEAT PUMPS 3 Sheets-Sheet 2 F|G.4. F|G.5.

TO EXPANSION 5 To o n P VALVE f 39 I8 E 4 4 L i 13% V// 4s 48 U |5 s4 FROM EXPANSION FROM OUTDOOR VALVE 00V COOLING POSITION F|G.6 F|G.7.

FROM INDOOR vTo EXPANS 3 con. ION

,les 39 59 L 5 0 3 8 \W//////(A/A7/' HQ u, m 45 43 j 5%: \r 7777/70/16,

TO OUTDOOR 7 VALVE &

V HEATING POSITION |NVENTOR= JAMES R. HARNISH,

ATTORNEY Jan. 24, 1967 J. R. HARNISH 3,299,662

CHECK VALVE MEANS FOR HEAT PUMPS Filed Nov. 12, 1965 3 SheetsSheet 5 FIG.8. F|G.9.

T0 INDOOR TO EXPANSION COIL VALVE FROM EXPANSION FROM DOOR VALVE & V

COOLING POSITION FIG.IO F|G.||,' 56 g E TO EXPANSION r" 3| 56 49 \IQLV 39 57 2| \I/, /Z I 22 I 58 J 59 35 54 30 58 FROM EXPANSION TO OUTDOOR VALVE 0U V HEATING POSITION INVENTOR= JAMES RHARNISH, W DIWM ATTORNEY United States Patent 3,299,662 CHECK VALVE MEANS FOR HEAT PUMPS James R. Hamish, Staunton, Va., assignor to Westinghouse Electric Corporation, Pittsburgh, Pa, a corporation of Pennsylvania Filed Nov. 12, 1965, Ser. No. 507,397 10 Ciaims. (Cl. 62-324) door coil and the expansion valve into the indoor coil when cooling is required, and for routing the refrigerant from the compressor through the indoor coil and the expansion valve into the outdoor coil when heating is required. Such a heat pump requires four check valves for routing the refrigerant in the proper directions.

This invention cornbinesthe functions of such four check valves in a single structure, reducing the number of tubing connections from eight to four, saving tubing and space, improving appearance, and reducing cost. In one embodiment of this invention, a cylinder has a piston slidable therein to two positions, and has four tubing connections, one to the outdoor coil, a'second to the indoor coil, and the third and fourth to the expansion valve. When the reversal valve is adjusted for cooling operation, refrigerant pressure automatically shifts the piston to one position in which the outlet of the outdoor coil operating as a condenser is connected to the inlet of the expansion valve, and the outlet of the expansion valve is connected to the indoor coil operating as an evaporator. When the reversal valve is adjusted for heating operation, refrigerant pressure automatically shifts the piston to its other position in which the outlet of the indoor coil operating as a condenser is connected to the inlet of the expansion valve, and the outlet of the expansion valve is connected to the outdoor coil operating as an evaporator.

Objects of this invention are to simplify and reduce the cost of a heat pump using a single expansion valve for cooling and heating operation.

This invention will now be described with reference to the annexed drawings, of which:

FIG. 1 is a refrigerant circuit schematic of a conventional heat pump;

FIG. 2 is a refrigerant circuit schematic of a heat pump embodying this invention;

FIG. 3 is an enlarged, projected view of the piston of the check valve cylinder of FIG. 2;

FIG. 4 is an enlarged side view, in section, of the check valve cylinder with its piston shown in cooling position;

FIG. 5 is a section along the lines 55 of FIG. 4;

FIG. 6 is a view similar to FIG. 4 but with the piston shown in its heating position;

FIG. 7 is a section along the lines 77 of FIG. 6;

FIG. 8 is an enlarged side view, in section, of another check valve cylinder embodying this invention with its piston shown in cooling position;

FIG. 9 is a section along the lines 9-9 of FIG. 8;

FIG. 10 is a view similar to FIG. 8, but with the piston shown in its heating position, and

FIG. 11 is a section along the lines 1111 of FIG. 10.

Referring first to FIG. 1 of the drawings, the suction side of a refrigerant compressor C is connected by a suction gas line 9 to a conventional reversal valve RV which is connected by a discharge gas line 10 to the dis- "ice charge side of the compressor C. The valve RV is connected by a line 11 to one end of outdoor air coil 12, and by a line 13 to one end of an indoor air coil 14. The other end of the coil 12 is connected by a line 15 to line 16 containing a check valve 17, and line 18 to the inlet of expansion valve EV. The line 18 is also connected by line 19 containing a check valve 20, and line 21 to the other end of the coil 14. The outlet of the valve EV is connected to line 22 which is connected by check valve 23 to the line 15. The line 22 is also connected by line 24 containing a check valve 25 to the line 21.

During the indoor air cooling operation of FIG. 1, the valve RV routes refrigerant gas from the compressor C, through the line 11 into the outdoor air coil 12 operating as a condenser coil. Liquid from the coil 12 flows through the lines 15 and 16, the check valve 17 and the line 18 into the expansion valve EV which supplies expanded refrigerant through the lines 22 and 24, the check valve 25 and the line 21 into the indoor air coil 14 operating as an evaporator coil. Gas from the coil 14 flows through the line 13, the valve RV and the line 9 to the suction side of the compressor C.

During the indoor air heating operation of FIG. 1, the valve RV routes discharge gas from the compressor C through the line 13 into the indoor air coil 14 operating as a condenser coil. Liquid from the coil 14 flows through the lines 21 and 19, the check valve 20 and the line 18 into the expansion valve EV which supplies expanded refrigerant through the line 22, the check valve 23 and the line 15 into the outdoor air coil 12 operating as an evaporator coil. Gas from the coil 12 fiows through the line 11, the valve RV and the line 9 to the suction side of the compressor C.

Referring now to FIG. 2 of the drawings, components of which have the same reference characters as corresponding components of FIG. 1, the suction side of compressor C is connected by line 9 to reversal valve RV which is connected by line 10 to the discharge side of the compressor C. The valve RV is connected by line 11 to one end of outdoor air coil 12, and by line 13 to one end of indoor air coil 14. The other end of the coil 12 is connected by line 15 to port 30 of valve cylinder 31. The other end of the coil 14 is connected by line 21 to port 32 of the cylinder 31. The inlet of expansion valve EV is connected by line 18 to port 33 of the cylinder 31. The outlet of the expansion valve EV is connected by line 22 to port 35 of the cylinder 31.

Referring now to FIGS. 37 of the drawings, the cylinder ports 30, 35, 32 and 33 are at the longitudinal center of the cylinder 31. The ports 30 and 32 are diametrically opposite; the ports 33 and 35 are diametrically opposite, and the common axis of the ports 36 and 32 extends per pendicular to the common axis of the ports 33 and 35. A piston 40 is slidable within the cylinder 31 to the left end of the latter as shown by FIG. 4, and to the right end of the cylinder as shown by FIG. 6. The cylinder 31 has an integral head 38 at one end (the right end of FIGS. 4 and 6), and has a removable head 39 at its opposite end.

The piston 40 has a head 41 at one end (the right end of FIGS. 4 and 6), spaced by a diametral partition 42 from an intermediate head 43 which is spaced by a diametral partition 44 extending at a right angle to the partition 42, from a head 45 at the opposite end of the piston. Passages 46 and 47 are formed between the inner surface of the cylinder wall and the partition 42, and when the piston is at the left end of the cylinder as shown by FIGS. 4 and 5, the passage 46 connects the ports 30 and 33, and the passage 47 connects the ports 35 and 32. Passages 48 and 49 are formed between the inner surface 6 of the cylinder wall and the partition 44, and when the piston is at the right end of the cylinder as shown by FIGS. 6 and 7, the passage 49 connects the ports 32 and 33, and the passage 48 connects the ports 30 and 35.

The intermediate head 43 and the end-head 45 of the piston 40 have aligned bleed passages 51) extending therethrough which connect with the passage 49. The intermediate head 43 and the end head 41 of the piston 40 have aligned bleed passages 51 extending therethrough which connect with the passage 46. When the piston is at the left end of the cylinder as shown by FIG. 4, and the reversal valve RV is adjusted to operate the indoor coil 14 as a condenser coil, high pressure refrigerant from the coil 14 flows, as shown by FIGS. 6 and 7, through the port 32 into the passage 47 and through the bleed passages 50 into the cylinder between the left cylinder and piston heads. At the same time, refrigerant previously supplied into the cylinder between the right cylinder and piston heads, flows through the bleed passages 51, passage 45, the port 30 and the line into the outdoor coil 12 operating as an evaporator coil. The pressure differential across the piston causes it tomove to the right end of the cylinder as shown by FIG. 6. When the piston is at the right end of the cylinder as shown by FIG. 6, and the reversal valve RV is adjusted to operate the outdoor coil 12 as a condenser coil, high pressure refrigerant from the coil 12 flows through the port 31} into the passage 48, and through the bleed passages 51 into the cylinder between the right cylinder and piston heads. At the same time, refrigerant previously supplied into the cylinder between the left cylinder and piston heads, flows through the bleed passages 50, the passage 49, the port 32 and the line 21 into the indoor coil 14 operating as an evaporator coil. The pressure differential across the piston causes it to move to the left end of the cylinder as shown by FIG. 4. i

A pin 54 extends through grooves in the peripheries of the piston heads 41, 43 and 45 and through a groove in the inner surface of the cylinder 31, and serves to prevent the piston from rotating during its axial movements.

In the operation of FIGS. 2 and 4-7, during cooling operation, the piston 40 is at the left end of the cylinder 31 as shown by FIG. 4. The reversal valve RV is in its cooling position, and routes discharge gas from the compressor C through the line 11 into the outdoor coil 12 operating as a condenser coil. High pressure refrigerant liquid from the coil 12 fiows through the line 15 into the port 31 and through the passage 46, the port 33 and the line 18 to the expansion valve EV which supplies expanded refrigerant through the line 22, the port 35, the passage 47, the port 32 and the line 21 into the indoor coil 14 operating as an evaporator coil. High pressure refrigerant from the passage 46 also flows through the bleed passages 51 into the cylinder between the right cylinder and piston heads for maintaining the piston at the left end of the cylinder, the refrigerant previously supplied into the cylinder between the left cylinder and piston heads having flowed through the bleed passages 50, the passage 49, the port 32 and the line 21 into the indoor coil 14 operating as an evaporator coil. Gas from the coil 14 flows through the line 13, the valve RV and the line 9 to the suction side of the compressor C.

When the valve RV is adjusted from its cooling to its heating position, it routes discharge gas from the compressor through the line 13 into the indoor coil 14 operating as a condenser coil. High pressure refrigerant liquid from the coil 14 flows through the line 21, the port 32, the passage 47 and the bleed passages 511 into the cylinder 31 between the left piston and cylinder heads. At the same time, the refrigerant previously supplied into the cylinder between the right cylinder and piston heads, flows through the bleed passages 51, the passage 46, the port 30 and the line 15 into the outdoor coil 12. The pressure differential across the piston causes it to move to the right end of the cylinder. Refrigerantliquidflows from the passage 49 through the port 33 and the line 18 to the expansion valve EV which supplies expanded refrigerant through the line 22, the port 35, the passage 48, the port 30 and the line 15 into the outdoor coil 12 operating as an evaporator coil. Gas from the coil 12 flows through the line 11, the valve RV and the line 9 to the suction side of the compressor C.

The embodiment of the check valve of FIGS. 8-11 is generally the same as that of FIGS. 4-7, and operates similarly. It isdifferent in that instead of having the bleed passages 50 in the piston heads 43 and 45, it has a bleed line 56 connected to the line 21 and through a bleed passage 57 in the cylinder Wall to the interior of the cylinder 31 adjacent to the inner surface of its left head 39, and in that instead of having the bleed passages 51 in the piston heads 43 and 41, it has a bleed line 58 connected to the line 15 and through a bleed passage 59 in the cylinder wall to the interior of the cylinder adjacent to the inner surface of its right head 38.

In the operation of FIGS. 8-11, when the reversal valve RV is adjusted to its cooling position to route discharge gas through the line 11 to the outdoor coil 12 to operate the latter as a condenser coil, high pressure refrige'rant liquid from the coil 12 flows through the line 15, the bleed line 58 and the bleed passage 59 into the cylinder 31 between the right cylinder and piston heads. At the same time, the refrigerant previously supplied into the cylinder between its left head and the left head of the piston, flows through the bleed passage 57 and the bleed line 56 into the line 21 connected to the indoor coil 14 operating as an evaporator coil. The pressure differential across the'piston causes it to move to its cooling position at the left end of the cylinder as shown by FIG. 8. Refrigerant liquid from the line 15 flows through the port 311, the passage 46, the port 33 and the line 18 to the expansion valve EV which supplies expanded refrigerant through the line 22, the port 35, the passage 47, the port 32 and the line 21 to the indoor coil 14. Gas from the coil 14 flows through the line 13, the valve RV and the line 9 to the suction side of the compressor C.

When the reversal valve RV is adjusted to its heating position to route discharge gas through the line 13 into the indoor coil 14 to operate the latter as a condenser coil, high pressure refrigerant liquid from the coil 14 flows through the line 21, the bleed line 56 and the bleed passage 57 into the cylinder between the left cylinder and piston heads. At the same time, the refrigerant pre viously supplied into the cylinder between the right cylinder and piston heads, flows through the bleed passage 59, the bleed line 58 into the line 15 connected to the outdoor coil 12 operating as an evaporator coil. The pressure differential across the piston causes it to move to its heating position at the right end of the cylinder as shown by FIG. 10. Refrigerant liquid from the line 21 flows through the port 32, the passage 49, the. port 33 and the line 18 to the expansion valve EV which supplies expanded refrigerant through the line 22, the port 35, the passage 48, the port 30 and the line 15 into the outdoor coil 12 operating as an evaporator coil. Gas from the coil 12 flows through the line 11, the valve RV and the line 9 to the suction side of the compressor C.

An advantage of the embodiment of FIGS. 8-11 is that when the piston is moved to the left end of the cylinder, it closes the bleed passage 57, compressing refrigerant between the left cylinder and piston heads, preventing metal-to-metal contact, and when the piston is moved to the right end of the cylinder, it closes the bleed passage 59, compressing refrigerant between the right cylinder and piston heads, preventing metal-to-metal contact.

What is claimed is:

1. In a heat pump having a refrigerant compressor; an outdoor heat exchanger; an indoor heat exchanger; reversal valve means connected to said compressor and to said exchangers for routing discharge gas from said compressor into said outdoor exchanger to operate-said outdoor exchanger as a condenser and for routing suction gas from said indoor exchanger operating as an evaporator to said compressor when cooling is required, or for routing discharge gas from said compressor into said indoor exchanger to operate said indoor exchanger as a condenser and for routing suction gas from said outdoor exchanger operating as an evaporator to said compressor when heating is required; and an expansion valve; the combination of a valve cylinder having a first port connected to said outdoor exchanger, having a second port connected to said indoor exchanger, having a third port connected to the outlet of said expansion valve, and having a fourth port connected to the inlet of said expansion valve; a piston slidably axially within said cylinder to first and second positions, said piston having first and second passages, said first passage connecting said first and fourth ports and said second passage connecting said second and third ports when said piston is in said first position, said piston having third and fourth passages, said third passage connecting said second and fourth ports and said fourth passage connecting said first and third ports when said piston is in said second position; and means for moving said piston to said first position when said reversal valve means operates said outdoor exchanger as a condenser, and for moving said piston to said second position when said reversal valve means operates said indoor exchanger as a condenser.

2. The invention claimed in claim 1 in which said cylinder has a first head at one end, and has a second head at the opposite end, in which said piston has a first head opposite to said first cylinder head and has a second head opposite said second cylinder head, in which said means for moving said piston to said first position comprises first means for supplying refrigerant from said outdoor exchanger into said cylinder between said second cylinder and piston heads and comprises second means for supplying refrigerant from between said first cylinder and piston heads in said cylinder into said indoor exchanger, and in which said means for moving said piston to said second position comprises said second means for supplying refrigerant from said indoor exchanger into said cylinder between said first cylinder and piston heads and comprises said first means for supplying refrigerant from between said second cylinder and piston heads in said cylinder into said outdoor exchanger.

3. The invention claimed in claim 2 in which said first means includes passage means in said piston connected to said first passage, and in which said second means includes passage means in said piston connected to said third passage.

4. The invention claimed in claim 2 in which said outdoor exchanger is connected to said first port by a first line, in which said indoor exchanger is connected to said second port by a second line, in which said first means comprises a first bleed line connected to said first line and to said cylinder between said second cylinder and piston heads, and in which said second means comprises a second bleed line connected to said second line and to said cylinder between said first cylinder and piston heads.

5. The invention claimed in claim 4 in which said piston and said bleed tubes are arranged so that said piston closes the connection of said second bleed tube to said cylinder when said piston is in said first position, and so that said piston closes the connection of said first bleed tube to said cylinder when said piston is in said second position.

6. In a heat pump having a refrigerant compressor; an outdoor heat exchanger; an indoor heat exchanger; reversal valve means connected to said compressor and to said exchangers for routing discharge gas from said compressor into said outdoor exchanger to operate said outdoor exchanger as a condenser and for routing suction gas from said indoor exchanger operating as an evaporator to said compressor when cooling is required,

the combination of a valve cylinder having a first port connected to said outdoor exchanger, having a second port opposite said first port connected to said second exchanger, having a third port between said first and second ports connected to the outlet of said expansion valve, and having a fourth port opposite said third port connected to the inlet of said expansion valve; a piston slidable axially within said cylinder to first and second positions, said piston having a first transverse slot connecting said first and fourth ports, and having a second transverse slot spaced transversely of said piston from said first slot connecting said second and third ports, when said piston is in said first position, said piston having a third transverse slot connecting said second and fourth ports, and having a fourth transverse slot spaced transversely of said piston from said third slot connecting said first and third ports when said piston is in said second position; and means for moving said piston to said first position when said reversal valve means operates said outdoor exchanger as a condenser, and for moving said piston to said second position when said reversal valve means operates said indoor exchanger as a condenser.

7. The invention claimed in claim 6 in which said cylinder has a first head at one end, and has a second head at the opposite end, in whichsaid piston has a first head opposite to said first cylinder head and has a second head opposite to said second cylinder head, in which said means for moving said piston to said first position comprises first means for supplying refrigerant from said outdoor exchanger into said cylinder between said second cylinder and piston heads and comprises second means for supplying refrigerant from between said first cylinder and piston heads in said cylinder into said indoor exchanger, and in which said means for moving said piston to said second position comprises said second means for supplying refrigerant from said indoor exchanger into said cylinder between said first cylinder and piston heads and comprises said first means for supplying refrigerant from between said second cylinder and piston heads in said cylinder into said outdoor exchanger.

8. The invention claimed in claim 7 in which said first means includes passage means in said piston connected to said first passage, and in which said second means includes passage means in said piston connected to said third passage.'

9. The invention claimed in claim '7 in which said outdoor exchanger is connected to said first port by a first line, in which said indoor exchanger is connected to said second port by a second line, in which said first means comprises a first bleed line connected to said first line and to said cylinder between said second cylinder and piston heads, and in which said second means comprises a second bleed line connected to said second line and to said cylinder between said first cylinder and piston heads.

10. The invention claimed in claim 9 in which said piston and bleed lines are arranged so that said piston closes the connection of said second bleed line to said cylinder when said piston is in said first position, and so that said piston closes the connection of said first bleed line to said cylinder when said piston is in said second position.

References Cited by the Examiner UNITED STATES PATENTS 2,750,764 6/1956 Lynch 62-460 2,875,780 3/1959 Martin 62324 3,024,619 3/1962 Gerteis 62-324 3,158,006 11/1964 Skeats 62324 WILLIAM J. WYE, Primary Examiner. 

1. IN A HEAT PUMP HAVING A REFRIGERANT COMPRESSOR; AN OUTDOOR HEAT EXCHANGER; AN INDOOR HEAT EXCHANGER; REVERSAL VALVE MEANS CONNECTED TO SAID COMPRESSOR AND TO SAID EXCHANGERS FOR ROUTING DISCHARGE GAS FROM SAID COMPRESSOR INTO SAID OUTDOOR EXCHANGER TO OPERATE SAID OUTDOOR EXCHANGER AS A CONDENSER AND FOR ROUTING SUCTION GAS FROM SAID INDOOR EXCHANGER OPERATING AS AN EVAPORATOR TO SAID COMPRESSOR WHEN COOLING IS REQUIRED, OR FOR ROUTING DISCHARGE GAS FROM SAID COMPRESSOR INTO SAID INDOOR EXCHANGER TO OPERATE SAID INDOOR EXCHANGER AS A CONDENSER AND FOR ROUTING SUCTION GAS FROM SAID OUTDOOR EXCHANGER OPERATING AS AN EVAPORATOR TO SAID COMPRESSOR WHEN HEATING IS REAUIRED; AND AN EXPANSION VALVE; THE COMBINATION OF A VALVE CYLINDER HAVING A FIRST PORT CONNECTED TO SAID OUTDOOR EXCHANGER, HAVING A SECOND PORT CONNECTED TO SAID INDOOR EXCHANGER, HAVING A THIRD PORT CONNECTED TO THE OUTLET OF SAID EXPANSION VALVE, AND HAVING A FOURTH PORT CONNECTED TO THE INLET OF SAID EXPANSION VALVE; A PISTON SLIDABLY AXIALLY WITHIN SAID CYLINDER TO FIRST AND SECOND POSITIONS, SAID PISTON HAVING FIRST AND SECOND PASSAGES, SAID FIRST PASSAGE CONNECTING SAID FIRST AND FOURTH PORTS AND SAID SECOND PASSAGE CONNECTING SAID SECOND AND THIRD PORTS WHEN SAID PISTON IS IN SAID FIRST POSITION, SAID PISTON HAVING THIRD AND FOURTH PASSAGES, SAID THIRD PASSAGE CONNECTING SAID SECOND AND FOURTH PORTS AND SAID FOURTH PASSAGE CONNECTING SAID FIRST AND THIRD PORTS WHEN SAID PISTON IS IN SAID SECOND POSITION; AND MEANS FOR MOVING SAID PISTON TO SAID FIRST POSITION WHEN SAID REVERSAL VALVE MEANS OPERATES SAID OUTDOOR EXCHANGER AS A CONDENSER, AND FOR MOVING SAID PISTON TO SAID SECOND POSITION WHEN SAID REVERSAL VALVE MEANS OPERATES SAID INDOOR EXCHANGER AS A CONDENSER. 